We had a release a few days ago for the HMI. We added an X/Y plot to the graphics engine. The X and Y axis are defined by files as well as up to 16 static data series.
The axis configuration and static series data are stored in comma separated text files to allow external programs to set the data values and the HMI to render the plot.
The axis can be any values as long as each tick is an increase to the previous tick. In other words, the data points for the axis can be linear or not. The plot uses an "F(X)" function to determine the correct point on the plot.
Up to 16 dynamic data points can be configured for each plot. One axis can be fixed if desired.
We made a short video, the link is on the web site, that covers the graphic element.